Cardboard package with a food product

ABSTRACT

A small and bright light-emitting device, comprising an outer boundary lens surface and at least one LED, is achieved by carefully choosing the inclination of each surface portion of the outer lens surface with respect to the chip size of the light source. The inclination of the surface portions are chosen such that the lens provides an optimal weighing between size and light efficiency.

The present invention relates to a package, especially a package for a food product having a rectangular block shape, such as a chocolate tablet for example.

In the following description, the term “wrap-around” pack will be used, which shall be considered as an equivalent to “envelope” pack.

Standard so-called “wrap-around” equipment for packing foiled tablets into carton board packs produces a pack which is not truly re-sealable and opened by a small side, like for example usual medicine cardboard packs.

In the tablet packs using this standard equipment, foil is folded around the tablet and then cardboard is folded around the tablet. The cards used are single sheets with perforations and fold lines. Once the consumer has opened the extra flap on the pack by breaking the die-cut perforations, there is no overlap to allow re-sealing.

Carton board packs exist with more complex multi-layer structures which would allow true re-sealing. However, these more complex packs are formed and erected before the wrapped tablet is inserted thereinto. This requires two separate operations: first, a wrapping machine is used for wrapping the inner pack, and second, a cartonning machine is used for erecting and filling the carton box with the wrapped tablet. Therefore, as can be understood, such tablets packaged into complex packs could not be manufactured on a conventional wrap-around packing line combining foiling and carton board packing.

Therefore, a need exists for a tablet cardboard packaging that can be produced with a standard foiling and cardboard-wrapping equipment as described above, said packaging being reclosable after the first opening.

The present invention addresses the problems set out above with a single-layer cardboard package for food products comprising a front panel, a back panel, four side panels, said front panel comprising precuts defining an openable portion of the front panel and a non-openable portion of said front panel, characterized in that:

(i) the non-openable portion of said front panel further comprises a locking slot, and

(ii) a locking element is fixed onto the openable portion of said front panel so as to extend its length, said element comprising a tongue portion to be inserted into said locking slot to lock said openable portion in the closed position.

In a highly preferred embodiment of the present invention, the locking element is a cardboard flat panel that is glued onto the openable portion of the front panel.

Preferably, the openable portion of said front panel is pivotable around the edge located between said openable portion and the adjacent side panel, said edge acting as a hinge.

Furthermore, said locking element preferably comprises an extension that forms a side panel of said package.

Said locking element preferably has a width that is equal to the width of said front panel.

In a preferred embodiment of the invention, the food product is a chocolate tablet.

Additional features and advantages of the present invention are described in, and will be apparent from, the description of the presently preferred embodiments which are set out below with reference to the drawings in which:

FIG. 1 is a schematic top view showing the two flat carton elements constituting the package of the invention.

FIG. 2 is a schematic top view similar to FIG. 1, showing the elements of the flat carton glued together;

FIG. 3 is a perspective schematic top view of the package of the invention, in the formed configuration, and in the closed position;

FIG. 4 is a perspective schematic enlarged view of the top portion of the package according to the present invention, in its closed position;

FIG. 5 is a perspective schematic enlarged view, similar to FIG. 4, the package being in its open position.

As illustrated in FIG. 1, the package 1 according to the present invention is a single-layer cardboard package for chocolate tablet products (tablet not illustrated in the drawings).

It is formed out of a flat cardboard which is erected and formed on a conventional carton forming machine. The flat carton board as shown in FIG. 1 comprises a front panel 2, a back panel 3, four side panels 4.

The front panel 2 comprises precuts 5 (shown in dotted lines in the drawing) defining an openable portion 2 a of the front panel and a non-openable portion 2 b of said front panel 2.

Furthermore and according to the present invention, the non-openable portion 2 b of said front panel further comprises a locking slot 6, and a locking element 7 is provided, that is to be glued onto the openable portion 2 a of said front panel 2 so as to extend its length, as shown in FIG. 2.

As shown in FIGS. 1 and 2, said locking element 7 comprises an extension that forms the side panel 4 which is adjacent to the openable portion 2 a of the front panel.

Said locking element 7 comprises a tongue portion 8 to be inserted into the locking slot 6 of the front panel 2, in order to allow locking of the openable portion 2 a of the front panel, when the package 1 is in its closed position, as shown in FIGS. 3 and 4.

As can be seen in FIG. 2, said locking element 7 has a width w that is equal to the width W of the front panel 2 of the package.

The locking element 7 is a cardboard flat panel that is glued onto the openable portion 2 a of the front panel, as illustrated in FIGS. 1 and 2.

As can be seen in FIG. 5, the openable portion 2 a of the front panel is pivotable around the edge 9 located between said openable portion and the adjacent side panel 4, said edge acting as a hinge.

As a result, during the first opening, the consumer lifts the locking element 7 and the openable portion 2 b of the front panel that are glued together, so as to open the package 1. The openable portion 2 a is separated from the rest of the front panel 2 along the precuts 5, and the package in open position then appears in the configuration shown in FIG. 5.

To reclose the package 1, the consumer pivots the locking element 7 around the edge 9 and over the non-openable portion 2 b of the front panel, and then places the tongue portion 9 of the locking element 7 into the locking slot 6 of the non-openable portion 2 b of the front panel, as shown in FIG. 4.

The filling process for filling a chocolate tablet into a package according to the invention is described hereafter. The main steps are as follows, in order:

-   -   1) The naked tablets coming from the chocolate tablet         manufacturing process are fed by a conveyor belt into the         packaging machine to the first operation where an aluminium foil         that comes from a reel is cut in sheets and applied around each         tablet;     -   2) After wrapping around the tablet, the foil is hermitically         sealed in three sides (the fourth side is folded only);     -   3) The tablets wrapped in foil go the next stage (secondary         packaging with a carton board);     -   4) The carton board is provided as pre-cut sheets that are fed         into a “magazine”;     -   5) Each carton board sheet is pulled out by grippers from the         magazine and hot-melt spots are applied for the final close;     -   6) The carton board sheet is wrapped around the foiled tablet by         means of a the folding system (known in the art), and then glued         on each tablet;     -   7) The tablet secondary packaging (i.e. the carton board) is         completed by finishing the gluing process thought an exit plate;     -   8) The tablets are discharged into the machine exit (lateral         brushes).

It is important to note that by using the two-pieces carton board according to the invention—as described hereinbefore—there is no need for any modification of the packaging machine, from the magazine up to the final pack

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be covered by the appended claims. 

1. A light emitting device comprising: a light emitting element comprising a light emitting diode (LED), said element having an effective light emitting surface (1) with an effective diameter D_(E), and a lens (2) in optical contact with said surface and arranged to receive light originating from said light emitting element, wherein an outer boundary surface of said lens is curved such that, in any location on the outer boundary surface, at least one edge ray (11-14) from said effective light emitting surface is incident at an angle (θ₁-θ₄) greater than or equal to θ_(c)−χ2π(1−cos θ_(c)), wherein θ_(c) equals the critical angle of total internal reflection of said lens in a given medium, and χ≦9°/sr.
 2. A light emitting device according to claim 1, wherein said outer boundary surface (2) is further curved such that, in any location on the outer boundary surface, any edge ray (11-14) from said effective light emitting surface (1) is incident at an angle less than or equal to θ_(c)+δ, wherein δ≦12°.
 3. A light emitting device according to claim 2, wherein a height H_(L) of said lens is within a range of: [D_(E)/(2*tan(θ_(c)+δ)), D_(E)/(2*tan(θ_(c)−χ2π(1−cos θ_(c)))], where δ≦12° and χ≦9°/sr, and a radius R_(L) of said lens in a plane comprising the light emitting element is within a range of: [D_(E)/2, 1.2*D_(E)].
 4. A light emitting device according to any one of the preceding claims, wherein χ≦6°/sr.
 5. A light emitting device according to any one of the preceding claims, wherein χ≦3°/sr.
 6. A light emitting device according to any one of the preceding claims wherein δ≦7.5°.
 7. A light emitting device according to any one of the preceding claims wherein δ≦3°.
 8. A light emitting device according to claim 7, wherein a cross section of said lens in a plane comprising the optical axis of the lens is larger than the ellipse described by the equation: ${\left( \frac{x}{0.9 \cdot R_{L}} \right)^{2} + \left( \frac{y - y_{0}}{{0.9 \cdot H_{L}} - y_{0}} \right)^{2}} = 1$ and smaller than the ellipse described by the equation: ${\left( \frac{x}{1.1 \cdot R_{L}} \right)^{2} + \left( \frac{y - y_{0}}{{1.1 \cdot H_{L}} - y_{0}} \right)^{2}} = 1$ wherein: x are coordinates parallel to the surface of the light emitting element (1), y are coordinates orthogonal to the surface of the light emitting element (1), y₀ is a constant within the interval of [−0.1, 0.25], and y is larger than or equal to y₀.
 9. The device according to claim 3 wherein the aspect ratio of the lens (H_(L)/R_(L)) is in the range between 0.4 and 1.2.
 10. A light emitting device according to any one of the preceding claims, wherein said light emitting element further comprises a color conversion element arranged to receive light from at least a portion of said LED, to alter the wavelength of at least part of said received light and to direct at least part of said received and wavelength converted light towards said lens.
 11. A light emitting device according to claim 10, wherein said color conversion element is a phosphor containing layer, preferably coated on said LED.
 12. A light emitting device according to any one of the preceding claims, wherein said lens (2) has a refractive index such that the difference in refractive index between said lens and an outer medium surrounding said lens is between 0.2 and 0.85, preferably between 0.2 and 0.6, and even more preferably between 0.2 and 0.4.
 13. A light emitting device according to claim 12, wherein the refractive index of said lens (2) is between 1.45 and 1.85, the height of said lens (H_(L)) is between 0.45*D_(E) and 1.2*D_(E), the radius of said lens (R_(L)) is between 0.55*D_(E) and 1.2*D_(E), and the aspect ratio H_(L)/R_(L) is in the range [0.6;1.2].
 14. A light emitting device according to any one of the preceding claims, further comprising a second, substantially transparent, dielectric body in optical contact with the lens, wherein the refractive index of the further dielectric body is between 1.3 and 1.6, the difference in refractive index between the lens and the further dielectric body is between 0.2 and 0.4, and wherein the height of said lens (H_(L)) is between 0.2*D_(E) and 0.85*D_(E) and the radius of said lens (R_(L)) is between 0.5*D_(E) and 0.85*D_(E).
 15. A light emitting device according to any one of the preceding claims, wherein said light emitting element comprises at least two LEDs, which emit light within different wavelength ranges.
 16. A light emitting device according to any one of the preceding claims, further comprising a diffusing layer arranged outside said outer boundary surface.
 17. A light emitting device according to claim 16, wherein said diffusing layer is optically separated from said outer boundary surface.
 18. An optical system comprising a reflector and a light emitting device according to any one of the preceding claims.
 19. An optical system according to claim 18, wherein said reflector is a dielectric collimator, that reflects light based on total internal reflection.
 20. A method of designing a cross sectional shape of an outer surface of a lens in a light emitting element having a surface (41) with an effective diameter D_(E), comprising the steps of: providing a first point (A), which is separated form the surface of said light emitting element by a distance equal to D_(c)/(2*tan θ_(s)) along a direction orthogonal to said light emitting surface; providing a first line (42), which is parallel to the light emitting surface and which intersects said first point; providing a second line (43), which intersects said first line at said first point at a first angle (α); determining a second point (B), on said second line, such that at least one edge ray (14) from the light emitting surface intersects with said second line at said second point at an angle equal to θ_(s), and such that no other edge ray from the light emitting surface intersects at said second point at an angle larger than θ_(s), providing a third line (44) intersecting said second line at said second point at a second angle (β); determining third point on said third line, such that at least one edge ray from the light emitting surface intersects with said third line at said third point at an angle equal to θ_(s), and such that no other edge ray from the light emitting surface intersects at said third point at an angle larger than θ_(s), providing a smooth curve (45), which intersects said first, second and third points and which represents a cross section of said outer boundary lens surface, wherein θ_(s) is between θ_(c)−χ2π(1−cos θ_(c)) and θ_(c)+δ, where χ≦9°/sr and δ≦12.
 21. A method according to claim 20, wherein χ≦6°/sr and δ≦7.5°.
 22. A method according to claim 20, wherein χ≦3°/sr and δ≦3°.
 23. A method according to claim 15 or 16, wherein said steps of providing an additional line and determining a further point is repeated a predetermined number of times.
 24. A method according to any one of the claims 20 to 23, wherein said first and second angles (α, β) are within the range of 0.005° and 0.1°, preferably within the range of 0.01° and 0.05°.
 25. A method according to any one of the claims 20 to 24, which further comprises the step of scaling said provided smooth curve such that its proportions is kept constant. 